Make Util.inferContentType marginally smarter

Issue: #2513

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=150310349

demo/src/main/java/com/google/android/exoplayer2/demo/PlayerActivity.java

@@ -316,8 +316,8 @@ public class PlayerActivity extends Activity implements OnClickListener, ExoPlay
   }
 
   private MediaSource buildMediaSource(Uri uri, String overrideExtension) {
-    int type = Util.inferContentType(!TextUtils.isEmpty(overrideExtension) ? "." + overrideExtension
-        : uri.getLastPathSegment());
+    int type = TextUtils.isEmpty(overrideExtension) ? Util.inferContentType(uri)
+        : Util.inferContentType("." + overrideExtension);
     switch (type) {
       case C.TYPE_SS:
         return new SsMediaSource(uri, buildDataSourceFactory(false),

library/src/main/java/com/google/android/exoplayer2/util/Util.java

@@ -791,6 +791,18 @@ public final class Util {
   }
 
   /**
+   * Makes a best guess to infer the type from a {@link Uri}.
+   *
+   * @param uri The {@link Uri}.
+   * @return The content type.
+   */
+  @C.ContentType
+  public static int inferContentType(Uri uri) {
+    String path = uri.getPath();
+    return path == null ? C.TYPE_OTHER : inferContentType(path);
+  }
+
+  /**
    * Makes a best guess to infer the type from a file name.
    *
    * @param fileName Name of the file. It can include the path of the file.
@@ -798,14 +810,14 @@ public final class Util {
    */
   @C.ContentType
   public static int inferContentType(String fileName) {
-    if (fileName == null) {
-      return C.TYPE_OTHER;
-    } else if (fileName.endsWith(".mpd")) {
+    fileName = fileName.toLowerCase();
+    if (fileName.endsWith(".mpd")) {
       return C.TYPE_DASH;
-    } else if (fileName.endsWith(".ism") || fileName.endsWith(".isml")) {
-      return C.TYPE_SS;
     } else if (fileName.endsWith(".m3u8")) {
       return C.TYPE_HLS;
+    } else if (fileName.endsWith(".ism") || fileName.endsWith(".isml")
+        || fileName.endsWith(".ism/manifest") || fileName.endsWith(".isml/manifest")) {
+      return C.TYPE_SS;
     } else {
       return C.TYPE_OTHER;
     }